The removal of unwanted and/or life threatening biological material from interior portions of bodily cavities, such as organs, vessels, articular joints and structures, sinuses, and various bodily lumens, is a very common procedure in various medical specialties and disciplines, such as pulmonology, cardiology, urology, gynecology, gastro-enterology, neurology, otolaryngology, orthopedics, and general surgery. Accordingly, various instruments and methods have been employed to perform these procedures, which are generally well known in the art.
One of the most important complications in such procedures is bleeding. The bleeding and resulting morbidity of tissue that occurs in many of the currently known surgical procedures is the result of abrasive, traumatic, and invasive excising and removal techniques. Many of these techniques risk perforation of the vessel or lumen in which the procedure is being performed, resulting in grave complications for the surgeon and patient. In addition, many patient maladies are simply not remedied by these procedures because no interventional, minimally invasive treatment modality exists, the methods are not efficient, safe, and reproducible, and/or the instruments employed lack the appropriate visualization, physiological measurement, and/or feedback necessary to ensure the safety, efficacy, and reproducibility of the procedure. Accordingly, a new type of treatment is required.
One instrument that is commonly used in various types of medical procedures is an inflatable balloon catheter. One particular application of such catheters is lung cancer. Among all types of cancer, this has the lowest survival rate, as more than one third of all deaths due to cancer are caused by lung cancer. Over 1.5 million new cases are diagnosed worldwide each year. The most frequent cause of death for lung cancer patients is airway obstruction. In lung cancer patients, one third of all cases initially, and another third of the cases in the long term, present main airway obstruction, which may cause asphyxia, hemorrhaging, and infection. These complications are the most frequent causes of death in lung cancer patients.
Use of interventional bronchoscopy for the treatment of lung cancer and the resultant airway obstruction increases the quality of life and survival rates of patients suffering from Chronic Obstructive Pulmonary Disease (COPD) and the obstructive co-morbidities associated with the cancer. Accordingly, balloon catheters have been routinely used with various endoscopes and with flexible and rigid bronchoscopes for dilation, as a tamponade to stop bleeding, and as an interference fixation device to hold instruments in place and prevent the retropulsion of those instruments under backflow pressure.
In light of the aforementioned need for a new type of treatment for removing undesirable biological material in bodily cavities, it has been realized that inflatable balloon catheters may further be employed as interventional tools for the excision and removal of such materials—such as endoluminal obstructions and tumors and endovascular occlusions—in various applications, such as the aforementioned interventional medical specialties of pulmonology, cardiology, urology, gynecology, gastro-enterology, neurology, otolaryngology, and general surgery. The use of balloon catheters in this way has presented a method of treatment that is simple, safe, highly effective, and inexpensive compared to other types of methods and devices that are used, such as mechanical, laser, electrocautery, cryotherapy, etc.
Accordingly, a new class of balloons has been suggested for this purpose, such as that disclosed in European Patent Application No. EP 1 913 882 by Karakoca. This device employs a balloon catheter with a hardening surface, which can be inserted into bodily cavities. After the device is inserted, the balloon is inflated, and the balloon is moved back and forth within the cavity such that the hardened surface performs a shaving action on the unwanted biological material. In this way, the targeted material is resected.
However, this particular instrument and method of using it suffers from a number of disadvantages and shortcomings. One of the most significant problems with this resector balloon is that unwanted biological material is removed by shaving it with the hardened surface on the outside of the balloon—i.e., by moving the balloon back and forth and/or rotating it. This mechanism of action can be abrasive and traumatic. Moreover, the hardened surface coupled with the shaving action can sometimes lack the precision necessary to prevent complications such as bleeding and structural perforation of the affected anatomical structure. Furthermore, the amount of torque and back and forth force needed on the balloon may cause a device failure, particularly where the balloon is attached to the catheter.
Another problem with this resector balloon is that it further lacks accuracy because it lacks the capability to precisely gauge the size of the environment in which it is being used to provide physiological measurements and feedback that could aid treatment intervention and efficacy. For example, there is no way for the surgeon to know the diameter of the affected bodily cavity itself, proximal or distal to the obstruction therein. Similarly, there is no way for the surgeon to know the intra-lumen diameter where the unwanted tissue growth or tumor resides, and further, no way to accurately adjust for changes in this diameter over time as the growth or tumor is resected. Because it has no mechanism for measuring the intra-lumen diameter at different points within the cavity, and particularly, how this changes over time, one is not able to properly adjust the amount of pressure supplied to the balloon and thereby prevent complications and expedite treatment.
A related problem with this device is that there is no way for a physician to measure the intra-articular space between two articular structures, endplates, or surfaces.
Yet another related problem with this device is that there is no way for the surgeon to know the density of the bodily cavity proximal or distal to the obstruction, nor can the surgeon know the density of the growth or tumor itself. Because there is no mechanism for measuring the density of the cavity or the obstruction, one is likewise unable to properly control the pressure in the balloon to aid surgical precision, minimize potential complications, and expedite the procedure.
Another deficiency is the inability to of conventional resector balloons to directly measure the diameter of the balloon and the cavity it is disposed in. Furthermore, conventional resector balloons cannot directly detect the tissue or fluid they are in contact with.
Yet another deficiency is the inability to control the balloon inflation pressure and thus the amount of safe radial force exerted on the lumen walls.
A further deficiency is that conventional resector balloons lack sufficient texture or friction to resect tissue efficiently. Furthermore, conventional resector balloons cannot adjust the amount of texture or friction of their resector surface in vivo or in real time. A further deficiency is the inability of known resector balloons to conveniently sample tissue for lab analysis or biopsy.
Another deficiency of known resector balloons is the inability to efficiently deliver energy to tissue. Energy delivery to tissue can help destroy the tissue or cauterize it to prevent bleeding or unwanted emissions of other biological fluids.
Accordingly, it has been proposed to control a resector balloon using a more advanced system, such as that disclosed in U.S. Patent Application No. 2010/0121270 by Gunday et al., the specification of which is hereby incorporated by reference herein in its entirety. In this type of system, a fluid source is used to inflate and deflate the balloon in pulsed fashion and can be operated according to presets that correspond to the resector balloon installed thereon, which allows for safe, precise resection that will not harm healthy tissue. The system receives operation feedback from the balloon, from which it can make relatively accurate estimations of the dimensions and other material properties of the material surrounding the balloon. Using these estimations, the system can adjust its operating parameters in real time to optimize the resecting procedure.
This type of system can be improved by using additional means of obtaining data about the resector balloon's environment, which can allow for more detailed and precise information about that environment and thereby facilitate improved control and optimization of the balloon's operating parameters, as well as improved feedback to the physician performing the operation.
What is desired, therefore, is a resector balloon system for removing undesirable biological materials that does not cause unnecessary trauma to the affected bodily cavity. What is also desired is a resector balloon system with controllable rates of inflation and deflation. What is also desired is a resector balloon system with independently controllable, conforming balloon geometries. What is also desired is a resector balloon system that is able to provide direct and accurate physiologic feedback to determine intra-lumen diameters and densities where the unwanted biological material resides and at locations proximal, distal and/or lateral to such material, the intra-articular space between two articular structures, and the type of balloon catheter connected. What is further desired is a resector balloon system that can be illuminated and imaged directly and indirectly, via radiopaque markers. What is also desired is a resector balloon system that is able to provide dimensional and performance metrics of the anatomy and the balloon catheter construct in vivo. What is further desired is a resector balloon that can accurately and directly analyze tissue, detect balloon size and relate environmental factors such as temperature, pressure and flow rates. What is further desired is a resector balloon that can deliver energy and sound waves to tissue and enhance or adjust the friction of its resecting surface. What is further desired is a resector balloon that can conveniently extract and retain tissue for sampling/analysis.